Dr. Donna Posluszny's career goal is to develop an independent research program focused on designing and evaluating novel behavioral and psychosocial interventions to enhance cancer patient-family caregiver dyads'ability to adhere to complex medical regimens and improve patient physical health outcomes. The K23 award will enable Dr. Posluszny, who is an Assistant Professor of Medicine and a clinical psychologist, to take the necessary first steps towards this goal by providing training in medical regimen research in cancer;behavioral and psychosocial intervention development in the field of adherence research in cancer;and methodologies for conducting and analyzing longitudinal and interventional clinical research with patient and family caregiver dyads. Specifically, the five-yer training plan includes (1) formal coursework;(2) regular mentoring from mentors and consultants;(3) participation in seminars, workshops, and national conferences;(4) mentored research;and (5) clinical practice. The combination of Dr. Posluszny's clinical training, the expertise of her mentoring team, and the research environment of the University of Pittsburgh School of Medicine and University of Pittsburgh Cancer Institute will facilitate the successful implementation of the proposed training plan and research study. The research plan is devoted to the implementation of an independent project to evaluate patient and family caregiver adherence to the complex, multicomponent post- hematopoietic stem cell transplantation (HCT) during the first 100 days post HCT and the development and piloting of a patient-caregiver dyad-focused psychoeducational intervention, grounded in the principles of Problem-Solving Therapy, to enhance adherence to the post-HCT medical regimen. Specific aims are (1) investigation of how patients and caregivers divide the responsibilities associated with adherence to the multicomponent post-HCT medical regimen post-hospital discharge;(2) determination of rates of, key risk factors for, and patient health outcomes associated with nonadherence to the post-HCT medical regimen;and (3) development and preliminary evaluation of a pilot patient-caregiver dyad-focused psychoeducational intervention designed to decrease nonadherence to the post-HCT medical regimen. This application addresses the National Cancer Institute's continuing commitment to developing initiatives to understand the role of family in the cancer experience and improve patient health outcomes, and is unique in its dyadic focus on adherence. Collectively, the outcomes of this study will foster the identification of both adaptive and nonadaptive dyadic approaches to adherence to the post-HCT medical regimen and provide the groundwork and preliminary data for a psychoeducational intervention to improve adherence for HCT patients and their family caregivers, and thereby improve patient health outcomes.